Jagan,
Nothing conclusive can be said from the information you've provided. However, I think the issue may be that you're out of CPU. Do this to isolate. Check in task manager for CPU. If the 100%CPU usage is attributable to the sqlservr.exe then look in EM Current Activity to identify which threads (spid) are using so much CPU. If the spid running your data transfer jobs shows a lot of CPU activity -- a lot being 3,600,000 ms -- which is 1 hr of CPU time -- then the problem is excessive cpu on your jobs. If there are some other SQL Server threads running, then find out what these threads are doing.
Don't go the I/O subsystem or memory, until you have resolved your CPU problem.
Hope that helps.
Ben